Quick change cutting edge

ABSTRACT

A replaceable, quick change, segmented cutting edge assembly for a loader bucket or the like has a plurality of material engaging teeth which project forwardly from the bucket floor. The assembly comprises a plurality of easily handled, relatively small sections of bifurcated cutting edges. The sections telescopically engage the cutting edge support between the teeth and are mechanically retained on the support by interlock with encompassing protector means for the teeth. Replaceable protector and guard means are provided for the cutting edge support, teeth and lower portion of the loader bucket sidewalls. The ground engaging teeth do not extend below the lower surface of the cutting edge, which permits the bucket to be used for cleanup operations.

llnited States Patent [1 1 Lukavich [11] 3,851,413 [451 oec.3,1974

[ QUICK CHANGE CUTTING EDGE [75] Inventor: Paul James Lukavich, .loliet,Ill.

[73] Assignee: Caterpillar Tractor Co., Peoria, 111. [22] Filed: Sept.14, 1973 [21] Appl. No.: 397,102

Related US. Application Data [63] Continuation of Ser. No. 174,004, Aug.23, 1971,

abandoned.

[52] US. Cl...' 37/141 T, 37/142 R [51] Int. Cl E021 9/28 [58] FieldofSearch 37/141 R, 141 T, 142 R,

[56] References Cited UNITED STATES PATENTS 1,755,438 4/1930 Ferguson37/141 T 1,843,205 2/1932 Clark 37/141 T 1,872,307 8/1932 Lehman 37/141T 2,828,558 4/1958 Reinhard 37/141 T 2,831,275 4/1958 Kimsey et al37/141 T 3,085,635 4/1963 Livermore 37/142 R X, 3,093,917 6/1963Schroeder 37/141 T 3,098,532 7/1963 Dobratz et a1. 37/142 R X 3,307,2773/1967 Kondracki 37/141 R 3,358,569 12/1967 A'verette 37/142 R X3,426,459 2/1969 Petersen... 37/142 R 3,497,973 3/1970 Campbell 37/141 R3,536,147 10/1970 Norton et al 37/142 R X 3,550,293 12/1970 Helton37/142 R 3,550,691 12/1970 Davies 37/142 R X 3,621,594 11/1971 Hahn etal 37/141 T 3,643,357 2/1972 Benning et al. 37/141 R PrimaryExaminerRobert E. Pulfrey Assistant Examiner-E. H. Eickholt Attorney,Agent, or Firm-Phillips, Moore, Weissenbergcr, Lempio & Strabala 5 7]ABSTRACT A replaceable, quick change, segmented cutting edge assemblyfor a loader bucket or the like has a plurality of material engagingteeth which project forwardly from the bucket floor The assemblycomprises a plurality of easily handled, relatively small sections ofbifurcated cutting edges. The sections telescopically engage the cuttingedge support between the teeth and are mechanically retained on thesupport by interlock with encompassing protector means for the teeth.

Replaceable protector and guard means are provided for the cutting edgesupport, teeth and lower portion of the loader bucket sidewalls. Theground engaging teeth do not extend below the lower surface of thecutting edge, which permits the bucket to be used for cleanupoperations,

17 Claims, lflDrawing Figures PATENTELDEC 3:914 851M113 SHEEIT 10F 5INVENTOR PAUL J. LUKAVICH ATTORNEYS PATENTEL DEC 3.851 .413

- SHEET 2 0f 15 -TF a INVENTOR PAUL J. LUKAVICH BY I 97W 9MJXLZQQ+AVQATTORNEYS PATENTELUEB 31914 3851mm SHEU 30F 5 INVENTOR PAUL J. LUKAVICHW [W4 21%, PWYM ATTORNEYS BACKGROUND OF THE INVENTION 1. Field of theInvention This invention relates to a cutting edge arrangement andstructure protective means for loader buckets, scraper and the like.This invention relates specifically to a cutting edge arrangement thatis removably secured to the material engaging edge of the structure.Also, protective means are provided for the leading sidewalls and bottomof the structure.

2. Description of the Prior Art There are many different types ofearthmoving apparatus in general purpose material handling equipmentwith load. carrying containers or bowls which are loaded by being urgedinto the material. Bulldozers, loaders and scrapers are typical of suchequipment.

Equipment of this general type usually requires a high strength, wearresistant cutting edge to withstand the very hard, and/or abrasivematerials to which it is subjected. In many instances, the cuttingelements include a series of outwardly projecting teeth to facilitatethe loading peration. Such teethand the support for the teeth must bewear resistant and of high strength to avoid excessive breakage.

Replacement of the cutting elements due to normal wear or breakage hasresulted in a variety of constructions in which the cutting edges andteeth are attached to the supporting apparatus by easily disengageablemeans. The vast majority of these constructions has not been fullysatisfactory in several respects.

In particular, the forward projecting cutting edge of loader buckets is,in most instances, integral with the bucket. Replacement of the edgerequires that the cutting edge be burned from the bucket with anacetylene torch or the like. This requires considerable time andexpense; Also, the cutting edge being of generally onepiece constructionis extremely long and heavy, which creates a handling and safety problemto the installer. Approximately 50% to 60% of all loader buckets areequipped with teeth to improve penetration and decrease cycle time. Theteeth are normally comprised of adapters which'are' either bolted orwelded to the cut- ;ting edge with replaceable tips removably secured tothe cutting edge. The cutting edge is a high wear member, with wear onthe bucket somewhat reduced by the teeth.

Wear on a cutting edge equipped with the teeth is normally the greatestat a point midway between the adjacent teeth, with little or no wearadjacent to or immediately behind the teeth. This results in a scallopedapprear'ancc as the cutting edge wears and periodic replacement isrequired. The replaceable bucket teeth generally project slightlydownward below the lower surface of the cutting edge, thus providing anaggressive tooth action in the material. Also, the teeth in someinstances have support portions which extend below the cutting edge.This creates a problem when the bucket is working in areas where it isdesirable to provide a substantially smooth surface, void of anydepressions or grooves formed by the plurality of bucket teeth. Also,when a bucket of this type is working in such areas as steel mills whereit is necessary to pick up material at floor level, this cannot beaccomplished with the teeth extending below the cutting surface.

It has also been found that wear on the teeth occurs generallyhorizontal with the bottom surface of the bucket. If the operator is notobservant, the lower side of the tips wears through, permitting wear ofthe tip adapter. Installation of a new tooth on a worn adapter createsan improper fit-up which, as a load is applied to the tip, may causefailure of the tip and/or adapter. Protection is also required for theleading edge of the bucket sidewalls in many severe applications toprevent excessive damage and relatively short life.

SUMMARY OF THE INVENTION This invention is a cutting edge assemblyproviding for ease of replacement in a compact structural arrangementwhich will reduce the downtime necessary to change the cutting edge. Theconstruction provides for means which will adequately protect the tipadapter, as well as retain the relatively small segments of cuttingedge. The bucket teeth of the invention are truly flush mounted withrespect to the lower surface of the cutting edge so that the bucket canbe used for cleanup operations. In the present invention, an easilyreplaced wear plate is provided between the ground and the structuralportion of the bucket adjacent the rear of the cutting edge section forprotection of the bottom of the structure Also, the present inventionhas removably secured protectors for the lower leading sidewalls of thestructure.

Other and further objects of the present invention will be apparent fromthe following description and claims and are illustrated in theaccompanying draw ings which, by way of illustration, show preferredembodiments of the present invention and the principles thereof and whatare now considered to be the best modes contemplated for applying theseprinciples.

Other embodiments of the invention embodying the sameor equivalentprinciples may be used and structural changes may be made as desired bythose skilled in the art without departing from the present inventionand the purview of the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings:

FIG. 1 is a perspective view of a portion of a general closing in detailthat portion of the subject invention;

FIG. 5 is a typical central cross sectional view of the replaceablecutting edge by itself; 7

FIG. 6 is a section view taken along lines VI-Vl of FIG. 2 disclosing indetail one of the retaining means for the cutting edge section;

FIG. 7 is a view taken along line VII-VII of FIG. 4 showing in detailthe upper retaining means of the sidewall guard.

FIG. 8 is a partial end view of a loader bucket disclosing an alternateembodiment of sidewall guard.

DESCRIPTION OF THE PREFERRED EMBODIMENT tegrally therewith. A chamfer 22extends along the upper leading edge of support 20.

A plurality of wedge-shaped forwardly extending teeth 24 comprised ofadapters 26 and replaceable tips 28 are secured to the top surface ofthe support 20 such as by welding in a spaced arrangement. The adapters26 are manufactured by any one of a number of different processes suchas forging, casting or fabrication. The two outer adapters 26' arewelded to the sidewalls 16.

The number of teeth 24 secured to the cutting edge varies with the sizeof the loader bucket and its application.

A plurality of relatively small, lightweight, wedgeshaped, bifurcatedcutting edge sections 30 telescopiclly engage the leading chamfered edgeof the support 20 between the adapters 26 and 26'.

A typical cross section of the cutting edge is shown in FIG. 5.

The sections 30 are comprised of upper and lower spaced parallel flangedwalls 32 and 34 joined at their forward ends by a wedge-shaped forwardend 36. The internal profile of the sections 30 conforms closely to theleading forward edge of support 20. The lower flanged wall 34 of thecutting edge sections 30 has outer ends 38 extending approximatelyhalfway under the adapter 26-26 below the support 20. The outer ends 38of adjacent sections 30 closely abutt one another to form asubstantially continuous wear surface below the support 20 forprotection thereof.

As best shown in FIG. 2, the central forward lateral leading edgeportion of end 36 of each cutting edge section 28 is of generallyarcuate shape extending substantially the full width of said section.Inner and outer end portions 40 and 42 respectively are interconnectedby the arcuate edge with the central arcuate portion disposed forward ofthe end portions. This is to provide additional wear material tocompensate for the normal scalloped wear pattern of a cutting edgebetween bucket teeth.

An equal number of adapter protectors 44 telescope over the forward endsof each adapter 26 and 26'.

The protector means 44 comprise a top wall 46, a bottom wall 48 and apair of generally vertical sidewalls 50 completely encompassing andcovering a substantial portion of each adapter forward of said cuttingedge support 20.

The two end protectors 44' for the end adapters 26' have a longitudinalslot 52 in their top walls 46' which engage the forward edge of theupwardly projecting sidewalls 16 of the bucket 12.

The relatively small individual sections of cutting edge 30 are retainedon the support 20 by an outwardly projecting, rearwardly facing U-shapedboss 54 and 54' on the sidewalls 50 and 50' of adapter protectors 44 and44'. The bosses 54 and 54 closely engage with the outer leading ends ofeach cutting edge section 30.

Slight manufacturing clearances are provided between the cutting edgesections 30 and support 20 as' well as between the protector bosses 54and 54' and the sections. Thus, the cutting edge sections 30 are notwedged tightly-on support 20.

The lower leading edges of the bucket sidewalls 16 are protected by areplaceable U-shaped guard 56. The guard 56 has a forward leading edge58 which is chamfered, as best shown in FIG. 7. As wear occurs on theguards 56 generally at the lower end, they are interchanged with oneanother and reversed end for end.

A recess 60' is provided in both ends of the guard sidewalls 62.

The upper end of the guard 56 is retained on the sidewall 16 of thebucket 12 by engaging the recesses 60 with an outwardly projecting pinor boss 64.

The lower end of the guard is retained by engaging with the longitudinalslots 52 in protectors 44.

The cutting edge assembly is installed in the following manner:

Guards 56 are installed on the bucket sidewalls 16 with their upper endsengaged with bosses 64.

The easily handled, relatively small, lightweight individual sections ofcutting edge 30 are telescopically fitted on the forward edge of thecutting edge support 20.

The protectors 44 and 44 are then telescopically fitted on the adapters26 and 26, retaining both the lower ends of guards 56 and sections 30.The bosses 54 and 54' on the protectors 44 and 44 engage with the outerends of the cutting edge sections 30 to lock them in position on thesupport 20 and also transfer a portion of the loads on the section intothe protectors 44 and 44' and adapters 26 and 26'.

.The protectors 44 and 44 are then removably secured to the adapters 26and 26' by a retaining pin 66.

As best shown in FIG. 3, the retaining pins 66 are retained in alignedapertures 68 and 69 in the protectors 44 and 44' and adapters 26 and26', respectively. A split spring ring 70 which is inserted in acounterbore 72 in the side of the adapter retains the pins 66.

Once the cutting edge sections 30 and the protectors 44 and 44 have beeninstalled forming a substantially straight cutting edge. the leadingwedge-shaped nose of the adapters 26 and 26' telescopically receive thereplaceable tips 28 which are of substantially conventionalconstruction. The tips 28 are removably secured on the adapters by aretaining pin 74 which is inserted in aligned holes 76 and 78 in theadapters 26 and 26' and tips 28, respectively. The retaining pin 74 isremovably secured by a split spring ring 80 which is located in acounterbore 82 in the side of the adapters 26 and 26'. It is recognizedthat retention of the protectors 44 and 44 and tips 28 could beaccomplished by several different types of conventional retainingdevices presently commmercially available.

The cutting edge support has a lower surface 84 g on which is removablysecured a sole plate 66. The plate 36 is secured by a plurality of plowbolts 83 and nuts 90. The sole plate E6 protects the lower surface 34 ofsupport 26 and provides a substantial amount of wear material below thesupport which must be worn away prior to any structural damage occurringto the bucket itself. r

The extreme forward ends of the bucket tips 28 do not extend below thelower surface of the cutting edge 11). With this arrangement, the bucketcan be used for cleanup operations where it is desirable to provide asubstantially smooth finished surface. The bucket can be worked in'areassuch as steel mills where it is desirable to pick up material at floorlevel, which would be impossible if the teeth extended below the bottomsurface of the bucket in an aggressive nature.

The sole plate 36 and replaceable cutting edge 10 protect the structuralcomponents of the bucket by providing a substantial amount ofreplaceable material which must be worn away prior to any possiblewearing of the structural components of the bucket. This, in combinationwith the true flush mounting relationship of the bucket teeth, cuttingedge and sole plate, would virtually eliminate the occurrence ofaccidental wear on the nose of the adapters 26 and 26', which woulddestroy the fitup of new tips 211 on the adapters.

FIGS. 8 and 9 disclose an alternate form of replaceable U-shapedsidewall guard.

In this arrangement, the upper end of the guard 56' isretained on thesidewall 16' by upwardly projecting ears 92 interlocking with aprojection 94 welded to the sidewall. The lower end of the guard 56' isretained on the sidewall by a quick change pin 96 which is inserted inthe aligned holes 98 and 100 in the guard and sidewall, respectively.The pin is retained by a split spring ring W2.

As wear occurs on the guards 56', they are reversed end for end on thesidewall whereupon cars 92' retain the upper end of the guard and thepin 96 is inserted through the holes 98' in the lower end.

1 16. 11) is a plan view of a right-hand portion of a quick changecutting edge according to this invention for aroclt bucket.

ln rock buckets, the central section of cutting edge extends furtherforward than the flanking side portions forming generally a V-shape forbetter engagement with and loading of rock.

The left half of the cutting edge is a mirror image of the right halfand employs adapters, adapter protectors and tips similar to that usedon the general purpose bucket of FIG. ll.

In this particular design a cutting edge support 1114 integral with thebucket has a straight central portion 106 normal to the direction oftravel of the bucket. Portion 1116 is flanked by a pair of outer endportions 108 having a plurality alternately angled sections 110 and aplurality of straight sections 112 which are parallel to the centralportion 106. The straight sections 112 are the location on which theadapters 26 and 26', which are similar to the various bucketconfigurations, are secured.

A tooth 114 is located on the longitudinal center line of the bucket andis flanked on each side by a quick change cutting edge section 311'.

Cutting edge sections 30' telescopically engage support 104 and areidentical to sections 30 of the general purpose bucket of FIG. 1.

A plurality of right-hand cutting edge sections 116 telescopicallyengage the right-hand rearwardly angled sections of the support 104between adjacent adapters.

The cutting edge sections 116 are comprised of inner and outer endportions 118 and 120 which are interconnected by a central portion 122.For purposes of conforming to the rearwardly angled sections 110 ofsupport 1 ll4l,-the cutting edge sections 116 are formed in an offset orskewed relationship from end to end.

It is desirable that the number of different parts required forapplication of the instant invention .to different bucket configurationsbe minimized. In the arrangement of FIG. 10 the adapters and protectorsare common and are identical to the outer adapters 26' and protectors44V disclosed in FIG. 1. It is recognized that all of the adapters andprotectors in FIG. 1 could also be identical to the outer adapters 26'and protectors 4141'. Theend portions 118 and 120 of sections 116 areaccordingly formed substantially identical to and dis-- forming thecentral portions 112 at an angle corresponding to the rearward angle ofthe sections 110 of the support 104. This construction-allows properfitup of the ends of the cutting edge sections 116 with the U- shapedbosses 54 and 54' of the protectors 44 and 44 such that the protectorsare common to various cutting edge support configurations.

The sections 116 are comprised of upper and'lower spaced parallelflanged walls 123 and 124 joined by central portion 122.

The outer ends 126 of the lower flanged wall 124 of the cutting edgesections 116 extend approximately halfway under the adjacent adaptersbelow the support and follows the general profile of the support.

A typical cross section of the cutting edge sections 116 correspondsgenerally to FIG. 5.

Corresponding left-hand cutting edge sections (not shown) are a mirrorimage of sections 116.

In a manner similar to the general purpose arrangement of FIG. 1, a soleplate 128 is removably secured to the bottom surface of cutting edgesupport 104 by a plurality of plow bolts 130 and nuts 132.

The sole plate 128 which follows the generally V- shaped profile ofsupport 104 provides protection for the support.

While we have illustrated and described the preferred embodiment of ourinvention, it is to be understood that these are capable of variationand modification, and we therefore do not wish to be limited to the aplurality of teeth secured to the cutting edge support in laterallyspaced relationship, a plurality of cutting edge sections mounted onsaid cutting edge support between the teeth,

wearable protector means having a lower surface positioned on saidsupport behind said teeth removably secured on each of the teeth withthe protector means engaging with and retaining the cutting edge sectionon said support, and

a lower wear surface comprising an extension of said cutting edgesection and extending behind the lower surface of said protector meansand forming a substantially planar wear surface with the lower surfaceof said protector means, the lower wear surface of said cutting edgesections extending substantially across said receptacle.

2. The assembly defined in claim 1 wherein said protector means comprisea top wall, a bottom wall and a pair of generally vertical side wallscompletely encompasses said teeth forward of said cutting edge support.

3. The assembly defined in claim 2 wherein an outwardly projecting bosson each of said walls of the protector engage with the cutting edgesection for retention of the section on the support.

4. The assembly defined in claim 1 wherein said teeth each comprise anadapter and a material engaging replaceable tip removably secured on theforward leading end of said adapter.

5. The assembly defined in claim 1 wherein said cutting edge sectioncomprises upper and lower spaced parallel flanged walls integral withand extending rearwardly from a wedge-shaped forward portion, with aninternal profile formed by the flanged walls conforming closely to theshape and size of said support and telescopically engaging the support.

6. The assembly defined in claim 5 wherein a plurality of said cuttingedge sections telescopically engage with the leading edge of saidsupport between adjacent teeth and forms a substantially straightcutting edge.

7. The assembly defined in claim 5 wherein the wedge-shaped forwardportion of thecutting edge section has a laterally extending leadingedge of generally arcuate shape extending substantially the full widthof said section, inner and outer end portions which are interconnectedby said arcuate edge with the central arcuate portion of the edgedisposed forward of the end portions.

8. The assembly defined in claim 5 wherein the lower flanged wall ofsaid cutting edge sections forms said extension of said cutting edgesections and extends laterally beyond the wedge-shaped forward portionunder the adjacent adapters below the support, with the ends of theadjacent walls in close relation to one another and forming saidsubstantially continuous wear surface below said support.

9. The assembly defined in claim 1 wherein the cutting edge supportsadditionally comprise a chamfer extending along the upper leading edgeof the support with a sole plate removably secured to the lower surfacefor protection of the support.

10. The assembly defined in claim 4 wherein the material carryingreceptacle is a loader bucket having a bottom, a rear wall and a pair ofsidewalls extending upwardly in parallelism from the opposite ends ofthe bottom.

11. The assembly defined in claim 10 wherein the two outermost adaptersare integral with the sidewalls of the loader bucket.

12. The assembly defined in claim 10 wherein a guard telescopicallyengages the lower leading edge of the bucket sidewall and is retained atits upper end by engagement with a projecting member on the sidewall andat itslower end by engagement with the protector for said outermostadapter.

13. The assembly defined in claim 12 wherein said guard is reversibleend for end on said sidewall.

14. The assembly defined in claim 10 wherein a guard telescopicallyengages the lower leading edge of the bucket sidewall with the upper endof the guard interlocking with a projection on the sidewall and thelower end retained by a pin removably secured in aligned holes in theguard and sidewalls.

15. In a material carrying receptacle of the class which is driven intomaterial to be loaded and which has a forward facing opening requiring acutting edge, a replaceable cutting element construction comprising:

a cutting edge support integral with the material carrying receptacleand having a straight central portion normal to the direction of travelof the material carrying receptacle and flanking outer end portionshaving alternatively rearwardly angled sections and straight sectionswhich are parallel to the central portion to form a generally V-shape,

a plurality of teeth secured to the cutting edge support in a spacedparallel relationship and parallel to the longitudinal center line ofsaid receptacle with the teeth on the outer end portions secured to saidstraight sections,

cutting edge sections mounted on the cutting edge support between eachpair of adjacent teeth, wearable protector means having a lower surfacepositioned on said support behind said teeth removably secured on eachof the teeth with the protector means engaging with and retaining thecutting edge sections.

a lower wear surface comprising an extension of said cutting edgesection and extending behind the lower surface of said protector meansand forming a substantially planar wear surface with the lower surfaceof said protector means, the lower wear surface of said cutting edgesections extending substantially across said receptacle.

16. The assembly defined in claim 15 wherein said cutting edge sectionsmounted on the angled portion of said support are comprised of inner andouter end portions which are interconnected by a central portionconforming to the rearwardly angled sections of said support, saidsections are formed in an offset relationship from end to end with saidend portions generally parallel to said teeth.

17. The assembly defined in claim 15 wherein the cutting edge supportextends substantially the full width of the material carrying receptacleand comprises upper and lower surfaces and a forward leading edge with asole plate removably secured to the lower surface of the support forprotection of the support.

1. In a material carrying receptacle of the kind which is driven intomaterial to be loaded and which has a forward facing opening requiring acutting edge, a replaceable cutting element construction comprising: acutting edge support integral with the material carrying receptacle, aplurality of teeth secured to the cutting edge support in laterallyspaced relationship, a plurality of cutting edge sections mounted onsaid cutting edge support between the teeth, wearable protector meanshaving a lower surface positioned on said support behind said teethremovably secured on each of the teeth with the protector means engagingwith and retaining the cutting edge section on said support, and a lowerwear surface comprising an extension of said cutting edge section andextending behind the lower surface of said protector means and forming asubstantially planar wear surface with the lower surface of saidprotector means, the lower wear surface of said cutting edge sectionsextending substantially across said receptacle.
 2. The assembly definedin claim 1 wherein said protector means comprise a top wall, a bottomwall and a pair of generally vertical side walls completely encompassessaid teeth forward of said cutting edge support.
 3. The assembly definedin claim 2 wherein an outwardly projecting boss on each of said walls ofthe protector engage with the cutting edge section for retention of thesection on the support.
 4. The assembly defined in claim 1 wherein saidteeth each comprise an adapter and a material engaging replaceable tipremovably secured on the forward leading end of said adapter.
 5. Theassembly defined in claim 1 wherein said cutting edge section comprisesupper and lower spaced parallel flanged walls integral with andextending rearwardly from a wedge-shaped forward portion, with aninternal profile formed by the flanged walls conforming closely to theshape and size of said support and telescopically engaging the support.6. The assembly defined in claim 5 wherein a plurality of said cuttingedge sections telescopically engage with the leading edge of saidsupport between adjacent teeth and forms a substantially straightcutting edge.
 7. The assembly defined in claim 5 wherein thewedge-shaped forward portion of the cutting edge section has a laterallyextending leading edge of generally arcuate shape extendingsubstantially the full width of said section, inner and outer endportions which are interconnected by said arcuate edge with the centralarcuate portion of the edge disposed forward of the end portions.
 8. Theassembly defined in claim 5 wherein the lower flanged wall of saidcutting edge sections forms said extension of said cutting edge sectionsand extends laterally beyond the wedge-shaped forward portion under theadjacent adapters below the support, with the ends of the adjacent wallsin close relation to one another and forming said substantiallycontinuous wear surface below said support.
 9. The assembly defined inclaim 1 wherein the cutting edge supports additionally comprise achamfer extending along the upper leading edge of the support with asole plate removably secured to the lower surface for protection of thesupport.
 10. The assembly defined in claim 4 wherein the materialcarrying receptacle is a loader bucket having a bottom, a rear wall anda pair of sidewalls extending upwardly in parallelism from the oppositeends of the bottom.
 11. The assembly defined in claim 10 wherein the twooutermost adapters are integral with the sidewalls of the loader bucket.12. The assembly defined in claim 10 wherein a guard telescopicallyengages the lower leading edge of the bucket sidewall and is retained atits upper end by engagement with a projecting member on the sidewall andat its lower end by engagement with the protector for said outermostadapter.
 13. The assembly defined in claim 12 wherein said guard isreversible end for end on said sidewall.
 14. The assembly defined inclaim 10 wherein a guard telescopically engages the lower leading edgeof the bucket sidewall with the upper end of the guard interlocking witha projection on the sidewall and the lower end retained by a pinremovably secured in aligned holes in the guard and sidewalls.
 15. In amaterial carrying receptacle of the class which is driven into materialto be loaded and which has a forward facing opening requiring a cuttingedge, a replaceable cutting element construction comprising: a cuttingedge support integral with the material carrying receptacle and having astraight central portion normal to the direction of travel of thematerial carrying receptacle and flanking outer end portions havingalternatively rearwardly angled sections and straight sections which areparallel to the central portion to form a generally V-shape, a pluralityof teeth secured to the cutting edge support in a spaced parallelrelationship and parallel to the longitudinal center line of saidreceptacle with the teeth on the outer end portions secured to saidstraight sections, cutting edge sections mounted on the cutting edgesupport between each pair of adjacent teeth, wearable protector meanshaving a lower surface positioned on said support behind said teethremovably secured on each of the teeth with the protector means engagingwith and retaining the cutting edge sections. a lower wear surfacecomprising an extension of said cutting edge section and extendingbehind the lower surface of said protector means and forming asubstantially planar wear surface with the lower surface of saidprotector means, the lower wear surface of said cutting edge sectionsextending substantially across said receptacle.
 16. The assembly definedin claim 15 wherein said cutting edge sections mounted on the angledportion of said support are comprised of inner and outer end portionswhich are interconnected by a central portion conforming to therearwardly angled sections of said support, said sections are formed inan offset relationship from end to end with said end portions generallyparallel to said teeth.
 17. The assembly defined in claim 15 wherein thecutting edge support extends substantially the full width of thematerial carrying receptacle and comprises upper and lower surfaces anda forward leading edge with a sole plate removably secured to the lowersurface of the support for protection of the support.